Fault Tolerance Design

Design fault tolerance for medical device software by applying patterns for detecting, containing, and recovering from faults scaled to your safety class. This satisfies IEC 62304 requirements for fault detection, redundancy, watchdog use, self-test, and error propagation control.

Graceful degradation in safety-critical control loops is implemented by defining strategies where the software operates in reduced capacity or enters a safe state when faults occur. This ensures continued safe operation during sensor or actuation failures.

Yes, Class C medical device sensing paths require redundancy and voting mechanisms to ensure accurate readings if one sensor fails. Redundant components and data paths are critical for higher safety classes to maintain reliable operation.

A watchdog mechanism for fault detection in medical devices monitors critical system resources and detects anomalies by requiring periodic signals from the software. If the signal stops, the watchdog triggers recovery actions or transitions the system to a safe state.

Yes, this approach applies to health monitoring and self-test in communication paths alongside sensing and actuation. It provides patterns for logging, alarms, and error propagation control across all critical paths defined by ISO 14971.

Fault tolerance patterns for lower safety class medical devices scale down redundancy requirements, focusing primarily on basic fault detection and safe states rather than redundant components. Higher safety classes require more comprehensive redundancy and voting strategies.